Dear List Members,
Perhaps the polarization in recent DRFa vs. Microdata discussions
might be resolved by looking more closely at the global needs that
such metadata systems are meant to satisfy. It seems to me that there
has been a focus on detailed differences, without adequately relating
these differences to the full range of the overall intent of metadata;
this lack of a high-level goal framework makes it more difficult to
analyze, defend, and aggregate various choices towards a final decision.
I see a resolution happening via the following (three-step) process:
A. Discuss the global metadata needs and rank them in order of
logical importance (a working list is given below). Achieve consensus
on such a list, independent of what system will be used to implement it.
B. Only then, compare RDFa and Microdata, separately, to the
global needs, to see what they satisfy well, poorly, or not at all.
C. Finally, on that basis, a comparison of RDFa and Microdata to
each other can be done, I think, successfully: it should be possible
to determine whether a particular relative strength of one or the
other occurs at a less important level in the overall global goals and
is thus of low relevance in the main decision (and can be ignored); or
occurs as part of a high level goal and thus stands out as being of
greater overall importance (and can't be ignored).
As a suggestion for starting Step A, here's my own preliminary list of
five global metadata goals.
+++++
Goals of a W3C-mediated Global Metadata System
(ranked highest importance first*):
1. To be created and to function in harmony with the existing W3C
core guidelines (patent-free, royalty free, open-standard, etc.)
2. To enable the creation of category names for data, so that
software display, manipulation, amalgamation, transfer, sale, and
other yet-unknown processes can be applied to the data on the basis of
those categories, independent of what could be done if software
attempted to examine only the data itself.
Such category names should be:
a) extensible, so that groups with any sort of need can create
category names relevant to their uses of data;
b) revisable, so that evolution in meaning of words or creation of
subdivisions can be easily accomplished;
c) universally accessible, so that any software with access to the
internet can make use of them.
d)...
3. To ensure the functioning of certain already-identified major
social needs for metadata, eg:
a) labelling of data that is intrinsically wordless, ie., audio files
and graphics;
b) intellectual collaboration and re-manipulation of data, ie., in
scientific research;
c) sale of digital services and digital goods, ie., purchase of web
services; purchase of digital works;
d) copyright and usage permission information for all types of works,
whether used freely or purchased;
e)...
4. To be as simple as possible in user interface (including both
coding language and logical organization), ie., to be relatively easy
to adopt by anyone capable of writing HTML, so that use of the
metadata system does not have a significantly higher barrier to entry
of either cost or expertise than HTML already entails.
5. To allow back-compatibility with previous (and current)
metadata solutions that have been applied to problems shown in step 3;
ie., vCard, microformats, etc....
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*The first goal, harmony with existing W3C policies, is unlikely to
need discussion, but I believe it is important to include it in its
proper position, before and enabling the other levels.
++++++
That's my offering. I hope it can be useful.
I'd like to add that before the need for this list of goals occurred
to me, I had some strong opinions in the RDFa/Microdata discussion.
But I now see that those were based on hasty conclusions that often
didn't consider at least some of the more important factors in this
list of goals. So I'm back to being neutral, and hopeful that having a
suitable group of people working through this list might end in a more
accurate choice.
Steven Rowat